CEES inhibits NO production and iNOS expression in LPS stimulated RAW264.7 macrophages. Panel A: Macrophages were simultaneously treated with various levels of CEES (as indicated) and low doses of LPS (as indicated). NO production was monitored as the concentration of nitrite in the culture medium after 24 h. Panel B: Cells were treated similarly as for Panel A; LPS, 10 ng/ml; CEES, 100, 200, or 300 μM (as indicated). Means not sharing a common letter are significantly different (p < 0.05). Nitrite levels in the culture medium (OD at 532 nm) were normalized to the amount of viable cells (OD of the MTT product at 580 nm). Panel C: Western blot analysis of iNOS protein from cells simultaneously incubated with 300 μM CEES and/or 10 ng/ml LPS for 24 h; cell lysates were prepared as described in Materials and Methods: Con, control cells; Pos, iNOS protein for positive control; Veh, vehicle; L, 10 ng/ml LPS stimulated cells; C, 300 μM CEES treated cells; L+C, LPS/CEES treated cells.